Over the weekend, a report from Reuters said that the FDA "stands ready" to work with companies developing Ebola treatments.

In its report, Reuters notes that the FDA's hold means Tekmira can't proceed with the trial placed on hold but doesn't prevent the company from initiating a new study proposal.

And were the company to initiate a new trial in people already infected with Ebola, "the benefit-risk ratio changes completely," an FDA source told Reuters. "Anything that would shift the risk-benefit to a more favorable outcome could potentially allow the authorization of that study," the source told Reuters.

Tekmira's treatment, TKM-Ebola, is currently being developed under a $140 million contract with the Department of Defense's Medical Countermeasure Systems BioDefense Therapeutics Joint Product Management Office.

Over the weekend, the first of two U.S. healthcare workers who contracted Ebola in Africa arrived in the U.S. The other is expected to arrive later this week.